By Andrew Osborn MOSCOW (Reuters) -In a few short hours in Alaska, Vladimir Putin managed to convince Donald Trump that a Ukraine ceasefire was not the way to go, stave off U.S. sanctions, and spectacularly shatter years of Western attempts to isolate the Russian president.

US President Donald Trump and Russian President Vladimir Putin held a high-stakes summit in Alaska on Friday, with both leaders describing the talks as productive, but offering few details on how to end Russia's war in Ukraine.